Methamphetamine injection or smoking ("ice") is increasingly causing severe stimulant dependence that is refractory to available pharmacological and outpatient psychotherapeutic treatments. In an open pilot trial, we evaluated the efficacy of a depot xanthene requiring infrequent IM administration, flupenthixol decanoate, for efficacy in withdrawal from smoking the very similar stimulant, cocaine. Ten poor prognosis, outpatient "crack" cocaine smokers were administered flupenthixol decanoate in an open-label, open-ended trial. Flupenthixol decanoate was well tolerated, and appeared to markedly and rapidly decrease craving and use, producing a 260% increase over prior treatment in these subjects in their average time retained in treatment. This application proposes a double-blind flupenthixol decanoate trial with a comparison to a current oral pharmacotherapy for stimulant abuse, desipramine. Ninety methamphetamine abusers will be treated in a clinical trial with randomized treatment comparing three contrasting pharmacological treatments added to conventional psychotherapy: (a) Placebo Desipramine plus Placebo I.M. Flupenthixol Decanoate (n=30) (b) Desipramine plus Placebo I.M. Flupenthixol Decanoate (n=30) (c) Placebo Desipramine plus I.M. Flupenthixol Decanoate (n=30). Outcome assessments will be comprehensive and multidimensional.